diff --git a/Documentation/doc/CMakeLists.txt b/Documentation/doc/CMakeLists.txt
index b711da2a0bb..ef63fe88760 100644
--- a/Documentation/doc/CMakeLists.txt
+++ b/Documentation/doc/CMakeLists.txt
@@ -26,13 +26,8 @@ else()
   set(CGAL_ROOT "${CMAKE_SOURCE_DIR}")
 endif()
 
-find_package(Doxygen)
-find_package(Python3 COMPONENTS Interpreter)
-
-if(NOT DOXYGEN_FOUND)
-  message(WARNING "Cannot build the documentation without Doxygen!")
-  return()
-endif()
+find_package(Doxygen REQUIRED)
+find_package(Python3 REQUIRED COMPONENTS Interpreter)
 
 #starting from cmake 3.9 the usage of DOXYGEN_EXECUTABLE is deprecated
 if(TARGET Doxygen::doxygen)
diff --git a/Documentation/doc/scripts/pkglist_filter b/Documentation/doc/scripts/pkglist_filter
index 2ec8ce96c9b..7912564df56 100755
--- a/Documentation/doc/scripts/pkglist_filter
+++ b/Documentation/doc/scripts/pkglist_filter
@@ -1,3 +1,3 @@
 #!/bin/sh
 
-exec ${PYTHON_EXECUTABLE} ${CMAKE_BINARY_DIR}/pkglist_filter.py "$1"
+exec ${Python3_EXECUTABLE} ${CMAKE_BINARY_DIR}/pkglist_filter.py "$1"
diff --git a/Documentation/doc/scripts/pkglist_filter.bat b/Documentation/doc/scripts/pkglist_filter.bat
index 83dff1aa121..1e716921c65 100644
--- a/Documentation/doc/scripts/pkglist_filter.bat
+++ b/Documentation/doc/scripts/pkglist_filter.bat
@@ -1,6 +1,6 @@
 @echo off
 
 :go
-${PYTHON_EXECUTABLE} ${CMAKE_BINARY_DIR}/pkglist_filter.py %1
+${Python3_EXECUTABLE} ${CMAKE_BINARY_DIR}/pkglist_filter.py %1
 
 @echo on